1. Field of the Invention
This invention relates to a row crop cultivator and a method of cultivating between rows of growing plants and, more particularly, to a cultivator and a method of cultivation with improved crop residue severing to reduce plugging, an improved middle worker and rapid adjustments.
2. Prior Art
Row crop cultivators were very important farm implements in the 1940s and 1950s for cultivating between rows of crops such as corn and soybeans. These implements continued to be manufactured in the '60s and '70s and occasionally a new row crop cultivator would be designed. The cultivators manufactured during those years had some common characteristics. They generally had a unit frame with a single gauge wheel, a disk coulter behind the gauge wheel, a middleworker behind the disk coulter and a provision for fenders or skirts to protect plants growing in the crop rows from soil thrown laterally by soil engaging tools. Space was provided between the gauge wheels and the coulter and between the coulter and the middleworker to allow residue lifted by the gauge wheel and by the coulter to fall back to the ground and to reduce plugging. A variety of tools were employed as middleworkers. The most common middleworker tool was a one piece V-shaped sweep commonly employed on field cultivators and chisel plows. The spacing between the three primary ground engaging components of each row unit resulted in the center of gravity of each row unit being spaced to the rear of a supporting tool bar some distance. The rear center of gravity problem could be accommodated when mounting some row cultivation units on the front of a tractor and others on the rear of a tractor. The center of gravity problem could also be handled by row crop cultivators that cultivated up to six rows on each pass through a field. The center of gravity location cannot be accommodated today with row crop cultivators cultivating twelve or more rows on each pass through a field. A tractor does not have sufficient weight to handle an old style row crop cultivator with twelve or more row units attached to a tractor-mounted rear tool bar.
The long row units were incapable of handling more than a minimal amount of residue on the surface of the ground. Until recent years, old crop residue on the surface of a field was not a problem. Moldboard plows turned residue under leaving the surface of a field relatively clean. Today, residue is generally left on the surface to reduce erosion, conserve moisture, and reduce cultivation costs. The old row crop cultivators could not handle the residue and would plug.
The sweeps used for middleworkers on old row crop cultivators tend to compress moist soil and residue into slabs and throw the slabs onto rows of growing crops. To prevent the slabs from killing plants in crop rows, fenders were provided. Row crop cultivators with long row units and fenders could not be pulled at speeds above about 3 or possibly 4 miles per hour without killing some plants growing in the crop rows.
The problems described above have, over the years, substantially reduced the use of row crop cultivators. Economics have dictated the use of primary tillage implements that leave trash or residue on the surface. Because of high surface residue and the high cost of cultivating growing crops at a slow speed, farmers have switched to chemicals for controlling weeds and grasses.
U.S. Pat. No. 4,834,189 on a row crop cultivator issued May 30, 1989 to the applicants of the improved row crop cultivator described below. This patent, which was based upon the Hiniker 5000 row crop cultivator, discloses a gauge wheel and disk coulter arrangement that can handle high residue conditions and a middleworker that substantially eliminates slabbing. The individual row units are short and compact making it possible to mount row units to cultivate 12 or more rows in one pass through the field. The cultivator also has an improved middleworker. These improvements incorporated in the Hiniker 5000 row crop cultivator have resulted in an implement capable of cultivating at 7 miles per hour or more without significant damage to a growing crop. The Hiniker 5000 row crop cultivator has given farmers an alternative to relatively expensive chemicals and in many cases the ability to reduce production costs. As a result, the Hiniker 5000 row crop cultivator has been very successful.